Rhenium: the essentials

Rhenium is silvery white with a metallic lustre; its density is exceeded only by that of platinum, iridium, and osmium, and its melting point is exceeded only by that of tungsten and carbon. It has other useful properties. It is expensive but useful as a trace alloying agent.

Rhenium does not occur as the free element in nature. Rhenium is found as minor components in the mineral gadolinite, which contains beryllium, and molybdenite, which contains molybdenum. In practice, it is extracted commonly as a byproduct from molybdenum smelter flue dust.

Isolation

Both Rhenium isotopes are used for medical purposes. Re-185 is used for the production of Re-186 which is used for bone pain palliation. Re-187 can be used for the production of Re-188 which is used for cancer therapy and restenosis, though most Re-188 is produced via W-186.